<http://www.w3.org/1999/02/22-rdf-syntax-ns#first>
<http://www.bbc.com/mundo/ultimas_noticias/2014/08/140801_ultnot_rusia_ley_internet_nc.shtml>
<http://www.bbc.com/mundo/ultimas_noticias/2014/08/140801_ultnot_rusia_ley_internet_nc.shtml>